Canada's Plant Hardiness Site

Maxent is a method for modeling species distributions by relating species occurrence data to one or more environmental variables. The idea of Maxent is to estimate a species' distribution by finding the distribution of maximum entropy (i.e., that is most spread out, or closest to uniform) subject to a set of constraints defined by the environmental conditions at the occurrence locations.

The method has a number of features that make it well-suited for species distribution modeling, including:

  1. using presence- only species data,
  2. allowing both continuous and categorical environmental variables,
  3. easily incorporating interactions between explanatory variables,
  4. providing model predictions in the form of probability of occurrence, and
  5. employing efficient deterministic algorithms that are guaranteed to converge to the distribution that maximizes entropy.

For the MaxEnt models presented here, we used the following 6 climate variables:

  1. annual mean temperature,
  2. maximum temperature of warmest month,
  3. minimum temperature of coldest month,
  4. annual precipitation,
  5. precipitation of warmest month, and
  6. precipitation of coldest month.

Click on this link for more details on Maxent and Maximum Entropy modeling.